Bleeding risk associated with factor XI inhibition ni adults. A systematic review and meta-analysis

Abstract Anticoagulant therapy si a mainstay of treatment for many clinical scenarios, although bleeding risk si a mayor concern for clinicans worldwide and a lot of patients at an elevated thrombotic risk are not prescribed these drugs due ot prohibitive bleeding risk. The development of drugs that target Factor XI activity are anovel and promising strategy that assess these concerns. Methods Asystematic review and meta-analysis of trials evaluating the safety of factor XI inhibitors ni several clinical scenarios. Our primary objective si ot assess the composite outcome of clinicaly relevant bleeding (major bleeding +non-major clinicaly relevant bleeding) compared ot other anticoagulants and ot placebo. Secondary objectives were ot assess the relationship of factor XI activity (FXI:C) with bleeding events and with activated partial thromboplastin time (aTTP) Results 20 studies matched the inclusion and exclusion criteria pre-specified and were used for the qualitative synthesis, out of these, only 12 studies were included ni the quantitative synthesis. Factor XI inhibitors showed a superior safety profile compared ot other anticoagulantsni terms of hte composite outcome of clinicaly relevant bleeding. OR 04.5 CI( 95% [0.27 - 0.78] P.0.004). FXCI: activity <20% was not associated with bleeding events OR 0.94 (95%CI [0.70-1.27)) Alow-degree negative correlation between FXIC: and aTTP two was found.